Would Heating an Aluminum Baseball Bat Make it hit Better

[TrippL]

Question came up this past weekend during a college baseball game. Would like to get some expert opinions on the subject.

A bat's deflection at impact acts like "trampoline" for the ball so heating up the bat could possibly make it deflect more, possibly giving it more spring. On the other hand , heat it up too much and it could dampen the impact. I would think heating it up could possibly improve the hitting distance of the bat.

What do you think?

 

[Twoballcane]

All of the energy from the player has to go into the ball in order to hit the ball as far as s/he can. Thus you want the bat to be as “stiff” as possible to transfer the energy. Any deflection (trampoline effect) will use up energy thus less energy to the ball. If no deflection, all of the energy will go into the ball, thus making the ball go further.

Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”

 

[Twoballcane]

Oh if you heat up the bat and then a sudden cool down may make the bat more brittle thus more stiff. So I guess if the player heats up the bat with a flame torch and then dip it in an ice bath just before going on just may give the player an extra edge, if s/he hits the ball at all LOL...



Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”

 

[TrippL]

Twoballcane,

Actually a stiffer bat will cause the ball to lose more energy due to internal friction whereas an aluminum bat momentarily stores the energy and returns it to the ball at impact.

http://www.hep.fsu.edu/~wahl/phy3091/sp05/talk1/AGomesTalk1.ppt

 

[TrippL]

Here's a more detailed explanation of the trampoline effect:

http://www.sgma.com/img/home/russell-tuned-bat.ppt

 

[ESPcomposites]

TrippL, you seem to be concerned about the trampoline effect and whether or not stiffer is better.

But what I don't understand is there is a reference that demonstrates the properties do not significantly change over reasonable temperatures. I would argue that manufacturing tolerances, processing, etc. would be a more significant affect.

What else can be reasonably said about it?



Brian

http://www.espcomposites.com

 

[Twoballcane]

Trippl, your correct, my apologies, I had it backwards.

Tobalcane
"If you avoid failure, you also avoid success."
“Luck is where preparation meets opportunity”

 

[unclesyd]

If as posted by the OP "they roll the bats to break the
fibers" you would have to talking about Fiberglass or Composite Bats

http://worthsports.com/bat-technology

 

[IRstuff]

But, it would seem plausible for someone to at least try sticking an aluminum bat into a pizza oven for a couple of hours and then see what happens. However, if there was a signficant change, that would be evident upon retesting of the BESR on that bat.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[TrippL]

IRstuff,

That's the point. The BESR testing does not specify a testing temperature as far as I can tell. Therefore a BESR approved bat could be tested at room temperature then heated to say 90 degrees F before you get up to bat by means of some type of heater and the bat could obtain properties that would surpass allowed BESR limits.

This is what happened during a college game last weekend. The batter got up to bat, hit then the catcher noticed the bat was "hot" to the touch so the bat was protested.

I would think that a bat manufacturer could design a bat to pass the BESR yet have better hitting properties (beyond BESR limits) when heated to say 90 degrees F. Nothing in the rules that say you can't heat a bat and no good way to enforce it.

Seems plausible to me.

 

[IRstuff]

If it's suspected that the bats are being tampered with, then the bat would be BESR tested at the tampering temperature, not at any other temperature. If the catcher indicated that the bat was hot to the touch, why would one test the bat's BESR at a normal temperature?

And this would not be that difficult to prove. A $20k thermal camera could be used to demonstrate that a team, or a player, is using a "hot" bat, and the measured tempeature from the thermal camera would then be used in the BESR testing.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[MintJulep]

Seems like a great topic for Myth Busters and their rigorously controlled scientific method.

 

[TrippL]

IRstuff,

Great reply IRstuff. Thermal camera is a great idea that I did not even think of. As for the BESR testing, I'm sure this will be addressed before next season at the BESR testing facility. However, don't think they can test them during a game. Great post though. Very helpful.

 

[TrippL]

And MintJulep, seems like a great topic for bat manufacturers who want to give sponsored teams a little under-the-table advantage.

Mythbusters is good idea too though.

 

[unclesyd]

There are a lot cheaper IR temperature measuring guns.

Maybe that I need to be in the bat warmer business like the used for race cars.

 

[ESPcomposites]

Exactly what mysterious property or event is supposed to occur by heating the bat?

For every 200F delta change there is about a 5% change in elastic modulus. There is a reliable source for this in Mil-Hdbk-5 or MMPDS. For the scenario indicated, there may have been about a 20F delta, and perhaps a 0.5% change in modulus.

This may lead to some very minor distance change, say 2-3 ft, but this would hardly be measurable, statistically relevant, or something a governing regulation would care about. Especially for college baseball...at least that would be my guess.

Is there any other real evidence, engineering source/property, etc. to indicate otherwise? There is nothing else provided in this thread. There really does not seem anything more to it than this. Is there a counter argument to what I have said?

Brian

http://www.espcomposites.com

 

[IRstuff]

Guns are cheaper, but they don't give you live video.

There's a big difference between testing for product compliance vs. testing for tampering. In the latter case, the investigator (say, me) would use the imaged thermal data to determine the temperature of the bat and test the BESR at that temperature. Any other temperature would be completely irrelevant to the investigation of tampering.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[IRstuff]

Speaking of thermal imaging, we had the occasion to image a wrecking ball during a demo, and impressively, we could see an increase thermal signature when the ball hit the concrete walls of the building being demo'd. Pretty cool to see thermal physics in action.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[Ron]

Well...you still have to hit the ball for any of this to work.
Swing batter batter batter swing.

 

[TrippL]

ESPcomposites,

I understand that that small of a change in the temperature of standard aluminum alloy will change the modulus of elasticity that small of an amount. However, how do you get from that to only a 2-3ft change in distance? What parameters are you using in your model? Bat speed? Ball speed? Ball coefficient of restitution? Bat length? Double wall or single wall bat? Thickness of aluminum? Flexibility in the handle of the bat? Etc...? Surely a bat could be physically designed that could take advantage of the small changes in the modulus of elasticity with temperature to maximize the transference from the bat back to the ball.

Also, surely there are numerous elements or types of alloys that have different properties which heating from 70F to 90 or 120F would maximize the delta in modulus resulting in maximized "trampoline" effect. Or if you prefer the maximum transference of kinetic energy back to the ball.

Looking for possibilities not limitations.

 

[TrippL]

Ron,

Very true.